Circular-knitting machine



July 15, 1930. T. s. GRIEVE I CIRCULAR KNITTING MACHINE Filed Jan. 19, 192B ill, 4 2 f C Patented duly l5, IQEQ were THOMAS SCOTT GRIEVE, OF LEICESTER, ENGLAND CIRCULAB-KNITTENG MACHINE Application filed January 19, 1923, Serial No. 247,826, and in Great Britain February '19, 1927.

This invention relates to circular knitting machines and concerns those of the type having co-aXial opposed needle cylinders and is applicable to both stationary and revolving 5 cylinder machines of this type and which operate also with an oscillating motion such for example, as for thefpurpose of making heels and toes in the production of seamless hosiery. The invention is an improvement 1 in or a modification of the invention described and claimed in the specification of my co-pending Serial No. 149,393, filed November 19, 1926.

As is well known, in machines of thetype 1 aforesaid, the needle cylinders are usually superposed the top one acting as the rib cylinder and the bottom one as the plain cylinder.

The objectof the invention is to provide for such machines improved meansto facilitate levelling up and knocking over of the rib loops as will be hereinafter described. r

A specific example of the improvement is illustrated in the accompanying drawing in which,

Figure 1 is a sectional elevation of such example and Figure 2 shows an improved holding down To enable knitting to takeplace upontwo or more adjacentrib needles without the cooperation of the opposing plain or frame needles, means have been provide'd to facili-' 'tate the action of the rib needles'in drawing sufficient to prevent the, yarn or web from:

slipping up over'the outer end of such. means. For eXa-niple, if the rib needles are working 7 in vertical tricks in the peripheral "edge of a ring or disc then thewalls of such tricks United States application,

-'pa rt,the essential feature of which is that its periphery while being formed to provide their loops and prevent the knitted web from should, if possible,project outwards between the needles to suchanextent as to constitute ledges which will hold the yarn or web down when the rib needles rise. A limitation'upon the extent of such projection is however, iniposed firstly by the necessity to provide clearr ance for the feeder and secondly and mainly by the necessity to provide clearance for the slack thread during reciprocating knitting as for instance when knitting the heel and toe of a stocking.

- Where the rib needles have operated in conjunction with a trick ring or some similar,- device in the top needle cylinder it has gen erally been found necessary to limit the'projection of the intervening walls or to round or bevel off the lower corner of such'walls for the purpose of preventing the slack thread from catching therein during reciproeating knitting, with the result that owing to the insuflicient projectionthere has been 'a tendency for the yarn or web to slip upwards over the outer edge during the'up-draw motion of the rib needles. V

The invention formingthe subject of the specificati'onbefore referred to was designed to overcome this difiiculty and accordingly provided in the top or rib needle cylinder of machines of the kind-referred to what is termed a collapsible trick ring or similar between the rib needles radial projections i which are of adequateextent to hold down the yarn or web, is collapsible or contractile in order to provide clearance when necessary and clear. the slack thread during reciprocating knitting. The operative'portion of the" periphery is constituted by holding down blades, bits or ]ike elements disposed radially between the rib needles and capable of ra dial movement. The important feature is" i that the bits or the'like are radially movable '(in contradistinction to the vertically-mov able sinkers or knocking-over b1ts previously mentioned) whereby they may occupy either a projected or extended position foruse 'or' a V iwithdrawn or. contracted position. Accord; j sing to one 'arrangementthe circular series of," 7 bits or like elements is contracted and ex flcc panded in part, i. e. in the region of the rib stitch cam only. That is to say those bits located near the rib stitch cam may be moved outto the projected position while the others reniain in the contracted position.

According to the present improvement or modification I employ aseries of holding down bits which have their outer ends bevelled, inclined or similarly formed to provide holding down edges for the yarn or web, and are posltioncd so that said edges are disposed horizontally. Conveniently said bits are straight and are carried slidably in a conical tricked bed or ring. The bits therefore operate on the angle and when withdrawn or retracted the horizontal holding down edges are correspondingly raised, thereby providi greater clearance for the thread.

U ccbrding to a convenient example the bits work in a ring one'side or face of which is made conical, i. e. inwardly bevelled, and tricked to constitute an interiorly conical bed for the reception of the bits, and the latter have; butts for engagement with a cam or -icguivaIent on or in an opposing conical earrler or bed, said cam being suitably arranged and ,designed to im art the required movement to the bits. onveniently the tricked faceor side of the ring isdis osed downwards withthecam carrier or b underneath. Accordin to the illustrative example the eudlpf eac bit 2. is bevelled and constitutes th holding down edge when the bit is in use. Thobitsare provided with butts 3 and work Fin tricks 4 inthe lower conical or bevelled facevnf a ring 5 locatedin the lower end of the to needle cylinder 6 and keyed to the inflict means of a key 7 and keyway 8.

The utts 3 project fromthe ring 5 into "a camtraok 9 provided on or formed in a conical bed 10 displaced below the ring 5. The said cam track is formed to retain the majority of the bits in the withdrawn position and represented at the right hand side waof Figure 1 to project those which are located in the vicinity of the rib stitch cam (not shown) as represented at the left hand side of figure. The cam bed is attached to a central sleeve 11 inthe needle cylinder which was fixed on a shaft 12and is turned, when re quilted, either frictionally by the cylinder or 5 positively in the manner fully set forth in the rior specification, to change the position cum 9 whereby bits in that portion of located during reciprocating knitting are and thus clear the thread.

Whatolaim then is L inlet circular-knitting machine of the WMWJ co-axial opposed cylinders in es-operute to produce rib fab ric,

inclined outer ends. and a conical tmekedhod whlch is mounted in the rib needle cylinder and whereby the said bits are carneedle circle where the slack thread is icireolnr series of straight holding down bits.

ried slidably so that their outer ends constitute horizontal holding down edges, said bits being slidable radially between the rib needles for respectively holding down the arn or web and providing clearance for the eeder, when necessary, and the slack yarn during reciprocting knitting, and means for effect ing the movement of the bits, for the purpose described.

2. In a circular knitting machine of the type having co-axial opposed cylinders in which needles operate to produce rib fabric, a circular series of straight holding down bits having butts and bevelled outer ends, aconical tricked bed which is mounted in the rib needle cylinder and whereby the said bits are'carried slidably so that their outer ends constitute horizontal holding down edges, said bits being slidable in and out between the rib needles, and a cam track for acting-on the butts whereby during circular knitting some of the bits are projected in the vicinity of the rib stitch cam for holding down the yarn or web while the remainder are kept withdrawn, saidcam track being movably arranged so that its position and the point at which the bits are projected can betehanged for reciprocating knit-ting to provide clearance for the feeder, when necessary, and the slack-yarn, for the purpose described.

3. In a circular knitting machine of the type having co-axial opposed cylinders in which needles operate to produce rib fabric, a circular series of straight holding down bitshaving butts and bevelled ends, a conical ring tricked onthe under side for the reception of. the bits and mounted in the rib needle cylinder so that the bits can slide radially inand out between the rib needles, a conical bed disposed below said ring, a cam track on saidbed for engagement by the butts whereby bits are projected in the vicinity of the rib stitchicamonly, during circular knitting,

for holding down the yarn or web, and a rotatable sleeve to which the conical cam bed is attached and which is operable to change the position of the cam for reciprocating knitting, and thereby change the point of pro-- j ection of the bits to provide clearance for the feeder, when necessary, and the slack yarn, for the purpose described.

4. In a circular. knittingmachine oi the type having co-axialopposed cylinders in which needles operate to produce rib fabric, a radially tricked conical bed in the rib needle cylinder, yarn or web holding elements formed with inclined ends and slidable in the tricks whereby horizontal holding down edges are provided, and meansfor eti'cciing projection and withdrawal of said elements between the-rib needles, for the purpose spec- In testimony whereof! aflix my signature.

THOMAS SCOTT GRIEVE,

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